Interior air can become very dry in the countries like Canada, Europe and Northern US during the winter months where forced air furnace heating systems are provided in many homes. The interior relative humidity level can drop to as low as 15% if the house is not equipped with a humidifier. Electrically powered furnace humidifiers are available but they are not entirely effective in bringing the humidity level to a comfortable level because furnace humidifiers are installed close to the heat source which makes them ineffective especially in a multiple story building; by the time heated air reaches the farthest level of the building the moisture level is reduced. A central humidifier cannot solve the problem in its entirety. A room humidifier can raise the relative humidity level of a room up to 50% by working locally.
Most modern day room humidifiers now on the market are electrically powered and must be plugged into a wall socket to operate, so there is cost involved in operating them. These electrically powered humidifiers have electrical motors therein which may emit an unpleasant noise. Because they contain complicated electrical devices inside, they are prone to breakdowns.
Room humidifiers that do not require electricity to operate are known, for example from the patents listed below. However, these humidifiers are usually designed to be used with one type of heating system (often radiators) and are not very versatile. Many of these prior art humidifiers tend to be cumbersome since they are bulky and take up a lot of space on the floor and may interfere with normal human activity in the room. They may also not be compatible for fixing onto the modern day forced air furnace vents. Also, because the water container in them is usually placed between the heat source and the absorbent material, these humidifiers are not very effective or efficient. Previously-known such humidifiers, including the ones mentioned below, may have one or more of the following drawbacks: A) their main water tanks are not detachable from the casings and portability of main water tank for refills becomes an issue; this makes refilling of the tank difficult and not practical for commercial market applications; and B) they have small tank capacity and need frequent refills; C) They are not a modular in design for easy manufacture or easily attachable to vents; D) The evaporative element is not stand alone and usually sits directly in the main water tank and evaporates directly from the main water tank, making it inefficient and difficult to maintain.
The following U.S. patents (and application) are representative of the prior art:    Appln. No 2002/0195728 published December, 2002, to Wooderson;    U.S. Pat. No. 7,828,275 issued November, 2010 to Won;    U.S. Pat. No. 6,850,698 issued February 2005 to Goh;    U.S. Pat. No. 5,403,233, issued April 1995 to Daneshvar;    U.S. Pat. No. 5,324,230 issued June 1994 to Hist;    U.S. Pat. No. 5,093,895 issued March 1992 to Ghorayeb;    U.S. Pat. No. 4,706,552 issued November 1987 to Maguire;    U.S. Pat. No. 4,338,859 issued July 1982 to Claytor;    U.S. Pat. No. 4,327,630 issued May 1982 to Brassine;    U.S. Pat. No. 4,307,656 issued December 1981 to Vesper;    U.S. Pat. No. 4,240,991 issued December 1980 to Shaub;    U.S. Pat. No. 4,226,174 issued October 1980 to Vesper;    U.S. Pat. No. 4,056,049 issued November 1977 to Stuckey;    U.S. Pat. No. 4,006,674, issued February to Culver, and    U.S. Pat. No. 27,461, issued March 1860 to McNeill.
The application of Wooderson, and the U.S. Pat. Nos. 4,706,552 to Maguire and 4,338,859 to Claytor, show devices which are largely or completely contained within the upper part of a floor register, and where the water tank is below floor level. This means that the water tank is small, and may be awkward to fill.
The humidifier disclosed in U.S. Pat. No. 7,828,275 to Won has the following drawbacks: a plurality of evaporating filters makes the humidifier costly to manufacture and also hard to maintain and also makes it costly to replace the evaporating elements. The many evaporating filters also make the evaporation rate high, relative to the reservoir size, which would require frequent re-fillings of the water tank.
The humidifier disclosed in U.S. Pat. No. 6,850,698 to Goh is a humidifier which has a main reservoir for holding water and for receiving an end of a paper towel while the other end is received by a rod located above and to the side of the reservoir, so that water wicks up the paper-towel through capillary migration and hot air passes over the moist towel. A paper towel is not an efficient and a rigid evaporating medium to humidify and to withstand the rough usage experienced in typical households. In this application the paper towel is partly exposed which makes it liable to damage, so this would need frequent replacement. The humidifier can only be used with a floor register and cannot be used with a wall register or vent. The apparatus is simply placed on the floor and is not positively located on the floor.
The humidifier described in U.S. Pat. No. 5,403,233 to Daneshvar is a rather fragile looking device used partly for decoration; the water trough is shallow and could not be expected to transmit much moisture to the evaporating elements.
The humidifier disclosed in U.S. Pat. No. 5,324,230 to Hist is a humidifier with an evaporating element which is exposed openly and not inside the casing, making it fragile. The main water tank is of low capacity and needs frequent refills for normal operation. The water tank is also open and exposed to the room and may be hazardous to kids and pets. It has a complicated installation mechanism for attachment to a wall. It can only be used with a wall register, and not with a floor register or vent.
The humidifier disclosed in U.S. Pat. No. 5,093,895 to Ghorayeb is designed for use with baseboard heaters, not for forced-air heating systems. It also has the problem that the main water tank does not detach from the casing and so is not portable for refills. This makes refilling the tank difficult and not practical for commercial market applications.
The humidifier disclosed in U.S. Pat. No. 4,327,630 to Brassine is too complicated, and has too many intricate fittings, to provide a marketable product. It uses a complicated evaporative member, and the construction involves many screws. It can only be used with floor register, and not with a wall register or vent.
The humidifier disclosed in U.S. Pat. No. 4,240,991 to Shaub has a humidifier with a rotating propeller, which may not work well with the draft provided by a forced air furnace, and could create a blockage to air flow. Noise from the propeller is also a negative factor. This also can only be used with wall register, and cannot be used with a floor register or vent. Its water tank is of low capacity and needs frequent refills.
The humidifier disclosed in U.S. Pats. Nos. 4,226,174 and 4,307,656 to Vesper have the following shortcomings: they can only be used with a wall register and cannot be deployed on residential floor vents connected to a forced air furnace. The insert material is bulky and can cause large mineral deposits from the water. The apparatus appears to be heavy and probably will not hang properly when the reservoir is filled with full capacity.
U.S. Pat. Nos. 4,056,049 to Stuckey and 4,006,674 to Culver both show types of apparatus intended to be used on floor registers, and having baffles which cause contact between the heated air and the top surface of a water tank. There is no filter element or like wicking element, so probably not much moisture is taken up by the air.
U.S. Pat. No. 27,461 to McNeill shows apparatus to be used with a wall register. The apparatus has parts which need to be fitted both above and below the register, which would make installation awkward.
Though the humidifiers of the type described above have been designed for humidifying heated air being forced into individual rooms, they seem to have met with minimal success in the commercial market due to lack of simplicity, lack of cost effectiveness, being hard to maintain, and not easy to install. Some have complex parts not designed to be mass produced at low cost, as is required for such apparatus to be employed in multiple rooms in a household.
Thus, it is apparent that there exists a need in cold countries for a non-electrically powered low cost humidifier which is easily compatible to be used with any types of modern day forced air heating systems (for example a natural gas furnace), which can be easily installed directly on the vents of rooms, is non-complex and easily maintainable, is simple in design and is also modular in allowing for different designs to be made with common components, environmentally friendly, highly efficient, easy to manufacture, light weight, compact and needing little space, is stable and rigid, and that such could be a success commercially.
This invention provides a new line of room vent humidifiers which fulfills at least some of these needs and potentially many other needs apparent to the skilled artisan in the relevant art.